DESCRIPTION (Applicant's Abstract): Ontogeny of Implicit Memory: Electrophysiological Evidence Studies with adults suggest that there are multiple memory systems, yet little is known about how this neurocognitive organization develops. This is unfortunate because any valid theory of memory must account for how the system matures and organizes. Specifically, researchers have proposed that implicit memory might be a functionally "earlier" developing system than explicit memory. In order to study the ontogeny of implicit memory, we propose to use event-related potentials (ERPs) with infants at 4-, 6-, and 8-months on a repetition priming paradigm. Priming occurs when a prior exposure to a stimulus affects how that stimulus is processed and interpreted at a later time. Changes in the timing or topography of electrocortical activity due to changes in repetition patterns will allow us to assess the different psychological factors that may influence memory performance. Moreover, this paradigm allows us to measure changes in cognitive activity without requiring any over behavioral responses by the infant. In order to facilitate our understanding of the development of implicit memory, adult participants will be run on a comparable paradigm.